Conventionally, a measurement device and sensor for electrochemically measuring blood glucose level has been put to practical use as an analysis device for easily analyzing the characteristics of body fluid.
As shown in FIG. 15, there is disclosed a measurement device 700 including an ejection lever 2 which is provided slidably to a measurement device body 1, and a slider (not shown) which moves in response to the ejection lever 2 to push out a sensor 200 (refer to Patent Document 1). The sensor 200 has a cavity (not shown) for collecting blood at its front end as shown in FIG. 17(a). An electrode and a reagent layer containing such as an enzyme and an electron carrier are provided in the cavity. Further, an electrode terminal 200a is provided at a rear end of the sensor 200.
The measurement device 700 has an electric circuit which applies a voltage to the electrode of the sensor 200 to measure a current value according to the glucose concentration in blood, which current is generated by a reaction between glucose in blood and the reagent layer, and the measurement device 700 calculates a blood glucose level according to the measured current value and displays the blood glucose level on a display 700a. 
FIG. 16(a) is an exploded perspective view of the conventional measurement device 700.
With reference to FIG. 16(a), in the measurement device 700, two claws 2a of the ejection lever 2 are inserted in a rectangle hole 1a of the measurement device body 1, whereby the ejection lever 2 is slidably attached to the measurement device body 1. The ejection lever 2 has a plastic spring 2b. 
A base plate 5 having a connector 16 is screwed to the measurement device body 1. The connector 16 has a pushing member 11. The pushing member 11 is fitted to a slider fitting part 2c of the ejection lever 2 through a notch 5a of the base plate 5 and a notch of the connector 16. Accordingly, the pushing member 11 is slidable along the longitudinal direction of the notch 5a in response to the ejection lever 2.
Hereinafter, the operation of ejecting the sensor 200 will be described with reference to FIG. 16(b). FIG. 16(b) is a cross-sectional view of the measurement device 700 in the state where the measurement device body 1, the ejection lever 2, and the base plate 5 shown in FIG. 16(a) are combined, wherein the long and thin sensor chip 200 for collecting blood is set in the measurement device 700.
In order to eject the sensor 200 after the sample such as body fluid is measured with the sensor 200 attached to the measurement device 700, initially, the ejection lever 2 is slid with a finger along the direction of an arrow shown in FIG. 16(b). Then, the pushing member 11 is also slid along the arrow direction in response to the ejection lever 2 and pushes the sensor 200 out of the connector 16, and thus the sensor 200 is ejected from the measurement device body 1.
Since the ejection lever 2 has the plastic spring 2b, when the sensor 200 is ejected by sliding the ejection lever 2, a force which urges the ejection lever 2 in the direction reverse to the sensor ejecting direction is generated by the plastic spring 2b. 
Further, as shown in FIG. 19, several electrodes (connection terminal) 14 included in the connector 16 may be positioned so as not to contact with a projection portion 11a of the pushing member in the connector 16 when the projection portion 11a is slid.
When the sensor 200 is ejected from the measurement device 700 by the ejection mechanism 700, the measurement of the blood glucose level by the measurement device 700 is completed.
In the conventional measurement device as described above, the operator can discard the sensor without touching the sample attached to the sensor, thereby avoiding infection of disease or the like. Further, since the sensor can be ejected by sliding the ejection lever 2, ejection of the sensor is facilitated.    Patent Document: Japanese Published Patent Application No. 2003-114213